Rock drill feed mechanism



July l5, 1941.

33 lef 24 3 /9/ 22 F f' if G. c. PEARsoN 2,249,716

RQCK DRILL FEED MECHANISM Y l Filed June 14, 1940 3 Sheets-Sheet l ATTORNEY.

Lex/MQW July y15, 1941. Q C, PEARSON' 2,249,716

ROCK DRILL FEED MECHANIS-M Filed June 14, 1940 s sheets-sheet 2 INVENTOR.

C. Peanson A TTORNE Y.

July 15, 194i.

G. c. PEARsoN 2,249,716

ROCK DRILL FEED MECHANISM Filed June 14, 1940 3 Sheets-Sheet 3 I N VEN TOR.

Gustav C. Peems'on BYa/ym A TTORNE Y.

Patented July 15, 1941 Roon DRILL FEED MECHANISM AGustav C. Pearson, Denver, Colo., assigner to Gardner-Denver Company, Quincy, Ill., a corporation of Delaware Application June 14, 1940, Serial No. 340,521

12 Claims.

This invention relates to improvements in rock drills and ismore particularly directed to mechanical means for feeding such drills to and from the work.

The principal object of the invention is to prof vide means whereby the drill may be automatically advanced according to the speedat which the drilling operation occurs, while maintaining the most desirable relation between the drill steel and the hammer piston of the drill. Another object of the present invention is to provide a feeding mechanism for a drilling Yunit which embodies two methods of control, both being automatic, one dependent upon the advancement of theV drill with respect to its work, while the other is solely under the control of the operator.

Another object of the invention is to provide a fluid actuated reciprocating element for moving the drilling unit longitudinally upon its support and such element being controlled by an element of the drilling unit.

Further objects of the invention will hereinafter appear, and to all of these ends the invention consists of the features `of construction, arrangement-of parts, and combination of elements, substantially as hereinafter fully described and claimed in the specification and shown in the accompanying drawings, in which:

Figure 1 is a longitudinal sectional view, partly f in elevation, showing a drilling unit with its feeding mechanism associated therewith.-

Figure 2 is a sectional View taken on the line 2 2 of Figure 1.

Figure 3 is a sectional view taken on the line 3-3 of Figure 1.

p Figure 4 is an Yenlarged perspective View showing the particular elements of the feeding mechanism.

Figure 5 is an enlarged detailed View showing the piston hammer control valve admitting motive fluid to the feeding mechanism, and

Figure 6 is a diagrammatic view illustrating the automatic valve for controlling the operation of the feeding mechanism and the piston hammer control valve permitting the flow of operating fluid to the automaticvalve. It also discloses, briefly, the association of the feeding mechanism and its automatic valve with the piston hammer valve.

Briefly the invention hereinabout to be described contemplates the provision of a fluid actuated means for moving a drilling unit to and from its work. In this particular instance the uid actuated means derives its motive' fluid from the throttle valve through a passageway having therein a valve actuated by the piston hammer of the drilling unit. The Clarkpatent, No. 1,733,402 of October 29, 1929, discloses a mechanism whereby the feeding of a drilling unit is controlled by the piston hammer but in this particular patent the operating fluid passingy to ,the feeding mechanism isla part of thefluid operating the drilling unit. y l Y The present invention differs from the Clark patent in that the operating fluid for the/feeding mechanism istaken directlyfrom the throttle valve -but in its passage to the automatic valve of the feeding mechanism, it is controlled by a valve actuated by the piston hammer andin vsuch an instance the operating fluid in the drilling unit is not disturbed.

yItis, of course, understood that the feedin mechanism shown may be of any desired type but one incorporating a reciprocating piston or element, for it has been found in the operation of such feeding mechanisms that the progress of the drill towards its work is more accurately maintained, insuring 'correctly the 'striking relation of the piston hammer with the steel. Such a mechanismis disclosed in the patent to Pearson, No. 2,115,231 of April 26, 1938, and it will be 0bserved that the feeding mechanism is one whereby the drill might be moved in any longitudinal direction upon its support, locked against movement or moved freely by hand.

The' present invention deals with a provision of means adapted to control the flow of operating fluid passing from a supply to the distributing valve of the feeding mechanism such means being actuated by a reciprocating hammer of the drilling unit. I'he specific means hereinafter disclosed is positioned in such a mannerthat it is operable upon both strokes of the reciprocating piston hammer, assuming, of course, that the hammer moves down to deliver its full vblow to the steel. When such action occurs thevalve is momentarily held open permitting the passage of fluid from the supply to the automatic distributing valve.

The invention further `contemplates' a structure wherein operating fluid for the feeding motor, while under control of the reciprocating piston hammer does not in any way impair the eiliciency `of the drilling unit. The fluid operating the feed motor is entirely independent of that operating the drilling unit, thus permitting both the operation of the feeding mechanism and the drilling unit under the most desirable conditions.

Furthermore the feeding mechanism may operate while the drilling unit is idle.

Referring to the drawings inv detail, particularly Figure 1, the numeral I9 indicates a conventional rock drill support having the usual cone II by which the support may be suitably secured to any type of mounting. As is customary the support includes upstanding side walls forming guideways for both the rock drill and its feeding mechanism and, while not shown, the support carries a rearwardly extension having a cross bar in which is xedly secured a feed screw I2. The front end of the feed screw is mounted in a conventional cross head I3 at the front end of the support. Slidable in the support isa rock drill I4 of any desired construction. In the present embodiment the drill I4 includes a cylinder I5 having the usual outstanding flanges, not shown, slidable and engaging in the upstanding walls of the support. The cylinder I5 has positioned therein the usual reciprocating piston hammer I6 intended to impart blows to a drill steel I1 supported in the front end ofthe drill. t The movement of the piston hammer within its cylinder I5 is controlled by an automatic valve I8 of any desired construction to which operating fluid is admitted through the usual passageways from a throttle valveindicated at I9.

Inerear of the valve AI8 and its supporting chest 20 is the usual ratchet means indicated at.2I for imparting rotary movement to theY hammer and ultimately to the drill steel I1. rTo move the drill I4 longitudinally of its support I0 there is arranged inV rear of the cylinder I5 a complete iluid operated motor indicated at 22. Briefly, the fluid operated 'motor 22 includes a suitable housing consisting of housing elements 23, 24 and 25 abutting one against the other and secured together by tie rods 26. The'housing of the feeding motor is maintained in place upon the rear ofthe cylinder I5 by the usual side rods 21 of the drilling unit. i

Positioned` within a cylinder formed by the elements 23, 24 and 25 is a reciprocating piston 28 controlled by an :automatic valve 29 disclosed in Figure 6 to which motive fluid is admitted either directly fromA the throttle valve I9 or through a passageway having therein the piston hammer control valve hereinafter described.

As disclosed in Figuree the reciprocating piston 28 includes oppositely projecting stems 30'and 3I, the former 39 having formed aboutitsperiphery straight flutes 32 engageable by the' hub of a gear 33. `The gear 33 meshes with a small pinion `34 rotatable about a fixed shaft 35 carried by the elements 24 and 25 and this gear 34 further meshes with an enlarged gear 3B formed exteriorly about one end of a sleeve 31'journaled for rotary movement within a bore formed within the elements'23 and 24. l The sleeve 31 is internally threaded to receive therein the threaded feed-screw I2 rigidly supported by the support I0.

The projecting stem 3I of the piston 28 is formed of two diameters, the larger of which has formed about its lperiphery spiral utes38, while the smaller diameter has formed 4about'its extremity spiral ilutes 39. From Figure 6 it will be observed that the spiral flutes 39 and 439 are oppositely arranged.

Engageable with the flutes 39' is `a ratchet ring 40 the hub -of which is internally fluted to receive the fluted portion 38 and positioned in rear of the ratchet Wheel 40 is a second ratchet Wheel 4I of the same diameter having its hub internally fluted to receive the fluted lportion 39 of the piston stem.

Engageable with the periphery of the ratchet ring 40 are spring pressed pawls 42 and 43 while the ratchet wheel 4I is similarly engaged by spring pressed pawls 44 and 45.

Normally all pawls are engageable with the peripheries of their respective ratchet wheels. However to control the'selective engagement of these pawls there is provided about each ratchet wheel an oscillating ring segment 43, each of which is provided with an external rack engageable by a common pinion 41 having 4a reduced portion or shaft projecting through the rear wall of the element 23 and upon this projecting end is aflixed a suitable operating lever.

As shown in Figures 2 and 3, it is of course obvious that when the pinion 41 is rotated by its operating lever in any selected direction, it assumes a position midway between the two pawls and upon the continued movement of the pinion in any direction it moves either the pawl 42 or 43 in Figure 2 from engagement with the ratchet 40 and at the .same time the corresponding one vof the pawls 44 and 45 is removed from engagement with its ratchet 4l. v

It is through the medium of these ratchets 40 and 4I that rotary movement is imparted to the piston 28 in its reciprocations and by reason of the gears 33, 34 land136 rotation is likewise fimparted -to the 'sleeve 31 moving'thefeeding unit longitudinally upon the support, and of course, thedrilling `unit in advance thereof.

Controlling the flow of operatingl fluidto the automatic valve 29 is the common throttle valve I9 so formed as to permit the flow of operating fluid to the valve I8 of the drill I4 and at the same time permitting the passage of fluid to a passageway 49 leading toa poppet valve '49 formed in the front end wall of the cylinder I5. Passing from the poppet valve 49 is a second passageway 5I leading to the supply port of the automatic valve.

The throttle valve is further provided with ports whereby the flow of operating uid to the drill and the passageway 48 might be interrupted to permit the passage of motive fluid from the valve through a passageway, 52 direct to the automatic valve 29. This position of the throttle valve is assumed when it is desired to move the rock drill longitudinallyof the support without operating the drill.

As disclosed in Figures 1 and 6 of the drawings the poppet valve 49 is provided with its usual stem resting upon a ball 59 confined within the wall `of the cylinder I5 in such a manner that a small portion of .the ball projects into thepath of the piston I9 reciprocating therein. From this structure it will be apparent that as the piston Il-reciprocates it will yengage the ball 59 lifting the poppet valve from its seat, permitting the flow of motive iluid through the passageway 48 to thepassageway 5I .leading totheautomatic valveZS. Itis further obvious that the valve 49 is held inthis open position by the piston until its stroke isreversed, thusholding for a limited period the poppet valve .49 in an open position, permitting the continued flow of motive fluid to the valve 29. In the event the piston hammer I9 should not 4for any particular reason complete its advancing stroke to contact the steel, the ball 59 is of course not engaged by the hammer and when such occurs the valve remains closed, thus the valve 49 only opens-when the piston moves to such a strike the steel.

The operating'valve 29 as disclosed in Figure 6 is merely of the piston type such as disclosed `in the Pearson patent mentioned above and has the supply passageways 55 and 56 leading to the front and rear walls of the cylinder within which the piston 28 reciprocates and controllable by the piston 28 are trip passageways 53 and 54 leading respectively to the front rand rear `ends of the piston valve. Thus ther valve 29 becomes an automatic valve operating to control the iiow of fluid active upon the piston 28.

Assuming now that the feeding mechanism as shown in Figures land 6 is in a position whereby movement of the mechanism and drill upon the support is desirable. To do this, the throttle valve I9 is movedrto the position shown in Figure 6 whereby motive, fluid from the valve is permitted to operate thevalve I8,` controlling the reciprocations of the piston hammer I6. As the piston hammer moves down the peripherial portion of its head, engages the ball 50 Ylifting the poppet valve 49 from its seat and permitting the passage of operating fluid from the throttle valve through passageway 48, poppet valve 49 and the passageway 5l to the automatic valve 29. the latter controlling its admission to the cylinder containing the reciprocating feeding piston 28 moving the same therein and imparting rotation to the sleeve 31. moving-the drill and feeding mechanism longitudinally of the support. It is of course apparent from the preceding description that the direction in which the drill moves is controllable by the selective means operating the various pawls engageable with the ratchet rings constituting a part of the feeding mechanism.

Inasmuch as the reciprocation of the piston hammer is rather rapid, a short impulse of motive fluid will be permitted to flow from the throttle valve to the automatic valve and on the first admission of this motive fluid to the automatic valve should the valve be in the position as shown in Figure 6, the fluid will be directed to the front face of the feeding piston moving the same backwardly. Should this impulse of motive fluid be insu'icient to move the piston its full stroke the piston will remain in an inactive position until the second impulse of motive fluid is admitted thereagainst by the operation of the poppet valve upon the second stroke of the piston hammer. This cycle continues until the piston 28 completes its full stroke. Continued impulses of motive fluid admitted into the cylinder will of course impart reciprocation to the piston 28.

Movement of the piston 28 may be interrupted or delayed due to the fact that in some periods of operation, the piston hammer may not complete its full stroke and when such occurs the poppet valve of course remains closed. It is only upon the completion of each down stroke of the piston hammer that the poppet valve opens and motive fluid is active upon the piston 28.

From the foregoing it is thought that the construction, operation and many advantages of the herein described invention will be apparent to those skilled in the art without further description, and it will be understood that various changes in the size, shape, proportion and minor details of construction may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.

position as todenmteiy vWhat I claim is: 1. In a feed mechanism'for rock drills, the combination of a support having movable thereon a drill, a reciprocating hammer piston ywithin the drill, a motor including a reciprocating piston for moving the drill on the support, an automatic valve controlling the flow of operating fluid to the motor'piston, a conduit vleading.' from a iiuid supply to the automaticl valve, a valve within the conduit, and said valve being held open by the hammer piston during a part of its movement in both directions.

2. In a feed mechanism for rock drills, the combination of asupport having movable thereon a drill, a reciprocating hammer piston within the drill, a piston motor for moving the drill on the support, a fiuid distributing valve lcontrolling the operation of the piston motor, a conduit leading from a iiuid supply to the distributing valve, and said conduit having therein a valve held open duringcertain movements of the hammer piston. v

3. In a feed mechanism forl rock drills, the combination of a support having movable thereon a drill, ahammerl piston reciprocating within the drill, iiuidy actuated means` moving the drill upon the support, Asaid means including a Yreciprocating member, an automatic valve controlling the flow of fiuid active upon said member, and an operable element positioned in advance of said valve and engageable by the hammer piston for controlling the flow of fluid to the fluid actuated means.

4. In a feed mechanism for rock drills, the combination of a support having movable thereon a drill, a hammer piston reciprocating within the drill, fluid actuated means moving the drill upon the support, said means including a reciprocating member, an automatic valve controlling the flow of fluid active upon said member, and an operable element positioned in advance of said valve and engageable by the piston hammer for controing the flow of uid to the valve and member.

5. In a feed mechanism for rock drills, the combination of a support having movable thereon a drill, a uid actuated motor moving the drill upon the support, said motor including a reciprocating member, an automatic valve controlling the flow of uid active upon said member, and an operable element positioned in advance of said valve and engageable by the piston hammer controlling the ow of fluid to the automatic valve and member.

6. yIn a feed mechanism for rock drills, the combination of a support having movable thereon a drill, a motor including a reciprocating element for moving the drill on the support, a commonvalve controlling the flow of operating fluid to both drill and motor, means actuated by the drill for further controlling the ow of fluid to the motor, and said common valve being movable to a position insuring the operation of the feed motor independently of the drill.

'7. In a feed mechanism for rock drills, the combination of a support having movable thereon a drill, a motor including a reciprocating piston for moving the drill on the support, an automatic valve controlling the reciprocations of said piston, a common valve controlling the flow of operating fluid to the drill and the automatic valve, a second valve in advance of the automatic valve functioning during the operation of the drill to control the flow of fluid to the automatic valve, and said common valve being movable to vinclude or exclude said second valve;v

8.-In a feed mechanism for' rock drills, the

combination of a supporthaving movable therel on a drill, a motor including a reciprocating element for moving the drill on the support, a common valve establishing communication-for the flow of operating fluid from a supply to the drill and motor, an actuated member between the valve and motor controlling theflow of fluid to the latter, and said commonvalve being movable to a position insuring the operation of the feed motor independently of the drill and the actuated member.

9. In a feed mechanism for rock drills, the combination of a support having movable thereon a drill, a motor including a reciprocating piston for moving the drill on the support, an automatic valve controlling the reciprocations of said piston, acommon valve controlling the flow of operating fluid to the drill and the automatic valve, a second Valve controlling the flow of operating fluid from the common valve to the automatic valve, and said second valve functionona drill, a motorincluding a reciprocating element for moving the drill on the support, a common Valve controlling the flow of operating uid to both drill and motor, an actuated member between the Valve and motor for further controlling the flow `of operating iiuid to the motor, and said actuated member functioning during the progress of drilling.

1'1. In a feed mechanism forrock drills, the combination of a support having movablefthereon a drill, fluid actuated means for moving the drill on the support, said means including a reciprocating member, an automatic valve controlling the flow of fluid active upon said member, and an operable element actuated during the operation of the drill for controlling the ficw of fluid to the valve and member.

12. In a feed mechanismfor rock drills, the combination of a support having movable thereon a drill, a motor including a reciprocating .element for moving the drill on the support, an

automatic valve controlling said element, a conduit for fluid from a supply to the-automatic valve, a controlling element Within the conduit, and said controlling element being actuated during the operation ofthe drill.

GUSTAV c. PEAasoN 

